Line feed alarm device for sprocket feed printer



1962 R. H. KARTASUK ETAL ,06

LINE FEED ALARM DEVICE FOR SPROCKET FEED PRINTER we HE lull II I.

INVENTbRS RAYMOND H. iKARTAsUK ROBERT s. WAMPACH Filed March '7, 1961ATTORNEY alarm device.

nited States atent r 3,065,336 LINE FEED ALARM DEVIQE FOR SPROCKET FEEDPRINTER Raymond H. Kartasuk, Lincoinwood, and Robert G.

Wampach, Roselle, Ill., assignors to Teletype Corporation, Slrokie,Ill., a corporation of Delaware Filed Mar. 7, 1961, Ser. No. 94,026 9Claims. (Cl. 197--133) This invention relates to line feed alarm devicesand lever assemblage 6 and a ratchet assemblage 7. The apparatus of thepresent invention is particularly adaptable to printing telegraphapparatus of the type illustrated in United States Patent No. 2,505,729,granted April 25, 1950 to W. J. Zenner and to United States Patent No.

2,667,256 granted January 26, 1954 to B. F. Madsen more particularly toline feed alarm devices for sprocket A feed printing telegraph pageprinter apparatus.

It is an object of the present invention to provide an alarm device forindicating the failure of a printer to advance the web being fed by it,upon receipt of a line feed si nal.

Another object of the invention is the provision of an apparatus whichwill indicate that the alarm device not operating properly.

Still another object of the invention is to provide an alarm device forindicating that a feed sprocket for'feed- 4 ing a web'of paper through aprinting telegraph apparatus has failed to advance the web. V

A feature of the present invention is the provision of an'auxiliarysprocket driven bythe paper, being fed by the sprocke't'feed'wheel of aprinter, for controlling an I -In accordance with one embodiment of theinvention a printing telegraph page or form printer of the sprocket feedtype is provided with a line feed alarm wherein, as

'the web of paper is fed step-by-step to the printing mechanism, itdrives an auxiliary sprocket having fixed to it a cam drum, and the linefeed bar which drives the regular paper feed sprocket of the apparatushas a pawl mounted on it for driving a ratchet wheel one step each timethe line feed bar steps the regular paper feed sprocket one step. Thecam drum on the auxiliary sprocket moves a retaining or check pawl outof operative association with the ratchet each time the auxiliarysprocket is ro- In the event the paper is not adevent that the supply ofpaper is exhausted, the auxiliary sprocket will not be stepped andconsequently, the pawl on the line feed bar will move the ratchetthrough a plurality of steps to carry a switch actuator on it intooperative relation to an alarm switch. The auxiliary sprocket is mountedon a latch lever that may be manipulated to return movement of theratchet wheel and cause operation of the alarm switch after apredetermined number of feeding operations by the line feed bar.

A more complete understanding of the invention may be had by referenceto the following detailed description when considered in conjunctionwith the accompanying drawings wherein:

FIG. 1 is a side elevational view of a portion of a printing telegraphapparatus showing the pertinent portion of the line feed mechanism andthe alarm mechanism associated therewith;

FIG. 2 is a fragmentary plan view of the apparatus shown in FIG. 1 takensubstantially along the line 22 of FIG. 1 in the .direction of thearrows, and

FIG. 3 is a fragmentary sectional view taken substantially along theline 33 of FIG. 1 in the direction of the arrows.

Referring now to the drawings, wherein like reference charactersdesignate the same parts throughout the several -views, the alarmmechanism of the present invention includes an alarm switch 4, anauxiliary sprocket 5, a reset which discloses and claims the details ofa line feed mechanism particularly useful in a structure such as thatshown in said Patent No. 2,505,729. The disclosure of the twoabove-identified patents is incorporated herein by reference and made apart hereof.

In the above-mentioned patent to B. F. Madsen, No. 2,667,256 there isshown a gear 11 fixed to a platen 12 which, as illustrated in saidPatent No. 2,667,256 is the usual smooth cylindrical platen but whichcould be provided with sprocket teeth 30 for feeding forms or othersprocket fed types of web. As described in said Patent No. 2,667,256 toB. F. Madsen, a pair of drive rack members or line feed bars 13 and 14are designed to alterrocked on a movable pivot 19 which carries a roller21 that cooperates with slots 22 and 23 in the line feed bars 13 and 14.The roller 21, as clearly described in said Patent No. 2,667,256 to B.F. Madsen, is mounted on a bell crank lever 24 biased about a pivot 25by a spring 26 and urged to engage an adjustable stop 27.

The alarm switch 4, auxiliary sprocket 5, reset lever assemblage 6 andratchet assemblage 7 are'mounted on a mounting plate 31 suitablyattached to the framework 23 of the printer apparatus, a pair ofmounting screws 32 being provided for mounting the plate 31. In theordinary operation of the apparatus disclosed in the above-mentionedPatent No. 2,505,729 to W. J. Zenner rotation of the platen 12 willwithdraw a webof paper 33 from a suitable supply thereof across a paperguide plate 34 to direct it to the platen 12. In the construction inaccordance with the present invention, a slot 35 is formed in the paperguide plate 34 into which the teeth 36 of the auxiliary sprocket 5 mayenter when the sprocket 5 is in the position illustrated in thedrawings. The sprocket 5 and a restoring cam 37 are rotatably mounted ona'stud shaft 38 which is fixed to a latch lever 40, the sprocket 5comprising aring suitably fixed on a shoulder 39 of the cam 37. Thelatch lever 40 is urged downwardly and to the right (FIG. 1) by acontractile spring 41 fixed to the mounting plate 31 and to the latchlever 40. An adjustable support 4-2 is adjustably mounted on themounting plate 31 and will serve to support the latch lever 40 in theposition shown in FIG. 1 where a bearing surface 43 on the latch lever40 engages the adjustable support 42, or in a position where a guidesurface 44 may rest on the support 42. The shaft 38 extends into a slot45 formed in the mounting plate 31 whereby the shaft 38 and theauxiliary sprocket 5 and restoring cam 37 may be moved upwardly from theposition shown in FIG. 1 to move the sprocket teeth of sprocket 5 out ofslot 35 thereby to facilitate the insertion of a Web of paper 33 intothe apparatus.

The restoring cam 37 cooperates with the reset lever assemblage 6, acamming portion 50 of which bears on the restoring cam 37. The resetlever assemblage 6 comprises two portions 51 and 52 adjustably connectedone to another by means of an adjustment screw 53 and the leverassemblage 6 is pivotally mounted on a pivot stud 54 suitably fixed tothe mounting plate 31. The lever assemblage 6 is urged to rock in aclockwise direction (FIG. 1) about stud 54 by a contractile spring 55fixed to the portion 51 of the lever assemblage 6 and to the mountingplate 31 thus, to urge the camming portion 50 of the assemblage 6 towardthe restoring cam 37'. The lower left-hand portion (FIG. 1) of the leverassemblage 6 has a check pawl 56 formed on it for cooperation withratchet teeth 57 on the ratchet assemblage 7 which assemblage isrotatably mounted on a stud shaft 58 fixed to the mounting plate 31. Theratchet assemblage 7 has fixed to it a switch actuator arm 65 having aswitch actuator 66 suitably fixed to it for cooperation with a switchbutton 67 on the alarm switch 4. The ratchet assemblage 7 is urged torotate in a counterclockwise direction about the stud shaft 58 by aspring 68 attached to a projection 69 on the lever 65 to carry aprojection 76 also formed on the-lever 65 into engagement with a stoppin 71 fixed to the mounting plate 31. In addition to the ratchet teeth57, the ratchet assemblage 7 is provided with two other sets of teeth 72and 73. The teeth 72 of the ratchet assemblage 7 are positioned forcooperation with a pawl 74 which is pivotally mounted on the upper endof the line feed bar 13 and is normally urged to rock about a pivot 75fixed to the bar 13 by a spring 76. The other set of ratchet teeth 73are aligned, with a check pawl 80 that is pivoted on the stud shaft 54and is urged to follow the movements of the reset lever assemblage 6 bya contractile spring 81 attached to the pawl 80 and the reset leverassemblage 6. This pawl is limited in its movement in a counterclockwisedirection (FIG. 1) by a projection 82 on it engaging a bent-over portion83 of the lever assemblage 6;

Operation In the operation of anapparatus equipped with the line feedalarm mechanism of the present invention a web of paper 33 may be fedinto association with sprocket teeth 30 of platen 12 of the printingapparatus by manually raising the lever 40 to move the surface 44-thereof into the position occupied by the surface 43 as shown in thedrawings, thus, to lift the shaft 38 restoring cam 37 and auxiliarysprocket upwardly to carry the teeth 36 of the sprocket 5 out of theslot 35 to permit free movement of the web of paper 33 underneath theauxiliary sprocket 5. After the paper has been fed across the plate 34to engagement with the teeth 30 of the sprocket teeth 30 of platen 12,the lever 40 may be restored to the position shown in the drawings wherethe sprocket teeth 36 will be engaged in sprocket feed holes 85 in theweb of paper 33. With the apparatus in this condition, that is, with webof paper engaging the platen 12 and auxiliary sprocket S, the initiationof a printing operation may take place and each time the web 33 isadvanced one step due to the reciprocation of the line feed bar 13, thepawl 74 will move the ratchet assemblage 7 one step. At each step ofmovement of the web'of paper 33, the ratchet assemblage 7 will oscillateone step. However, if the auxiliary sprocket 5 is moved in a clockwisedirection by the paper, the spring 68 will be permitted to snap theratchet assemblage 7 back to the position shown in the drawings due tothe fact that the cam 37 will cam the retaining or check pawl 56 oflever assemblage 6 out of engagement with the teeth 57 of the ratchetassemblage 7. Thus, for each step of movement of the web of paper 33 bythe line feed bars 13 and 14, the ratchet 7 will be moved in a clockwisedirection by the pawl 74 and then be returned in a counterclockwisedirection (FIG. 1) to the position shown in the drawings.

In the event that the webb 33 is not fed by the sprocket teeth 30 ofplaten 12 or the supply of paper is exhausted and as a result of thefailure to feed the paper or exhaustion of the stock of paper theauxiliary sprocket 5 is not rotated in a clockwise direction (FIG. 1),the retaining or check pawl 56 will engage with successive ratchet teeth57 and will thus prevent the spring 68 from returning the sprocketassemblage 7 to the position shown in the drawings. After apredetermined number of reciprocations are imparted to the line feed bar13, four in the apparatus illustrated, the switch actuator 66 will bemoved clockwise to engagement with the switch button 67 to actuate thealarm switch 4 calling an operators attention to the fact that thesupply of paper 33 is exhausted or that the line feed mechanism is notoperating properly. If a new supply of paper is to be placed in theapparatus, the lever 40 is manipulated to raise the restoring cam 37 andthereby rock the lever assemblage 6 counterclockwise (F-IG. 1) to permitthe ratchet assemblage 7 to move back to the position shown in thedrawings. Whereupon, a new supply of paper may be placed in theapparatus and the lever 40 restored to the position shown in thedrawings. If, by chance, the auxiliary sprocket and restoring cam areaccidentally left in the upward position with the guide surface 44engaging adjustable support 42, the check pawl will be rocked intoengagement with the teeth 73 on the ratchet 7 and if four steps ofreciprocation are imparted to the line feed bar 13 before this conditionis corrected, the check pawl 80 will cooperate with the ratchetassemblage 7 and the alarm switch 4 will be operated.

Although a specific embodiment of the invention has been shown in thedrawings and described in the foregoing specification, it will beunderstood that the invention is not limited to the specific embodiment,but is capable of modification and rearrangement, and substitution ofparts and elements, without departing from the spirit of the invention.

What is claimed is:

1. In a printer, line feed mechanism. including a feed sprocket foradvancing a web through the printer, a line feed member intermittentlyoperable fior imparting stepby-step rotation to said spocket, a storagedevice driven one step by said member each time said line feed member isactuated, means for returning said storage device to a normal position,means normally driven by the Web for causing operation of the returningmeans each time the line feed member drives the storage device one step,and alarm means actuated by said storage device following apredetermined number of operations of said member while the means drivenby the web is not driven.

2. In a printer, line feed mechanism including a feed sprocket foradvancing a web through the printer, a line feed member intermittentlyoperable for imparting stepby-step rotation to said sprocket, a storagedevice driven one step by said member each time said line feed member isactuated, means for returning said storage device to a normal position,means normally driven by the web for causing operation of the returningmeans each time the line feed member drives the storage device one step,and alarm means actuated by said storage device when said returningmeans is inoperative for a predetermined number of operations of saidline feed member.

3. In a printer, line feed mechanism including a feed sprocket foradvancing a web through the printer, a line feed member intermittentlyoperable for imparting stepby-step rotation to said sprocket, a drivepawl on said member, a ratchet driven from a normal position one step bysaid pawl each time said line feed member is actuated, means forreturning said ratchet to its normal position, cam means positioned tobe driven by the web for rendering the returning means operative eachtime the web drives the cam means one step, a switch actuating armcontrolled by said ratchet, and alarm means actuated by said arm upon apredetermined number of operations of said ratchet coupled with failureof said cam means to be driven by the web.

4. In a telegraph printer, line feed mechanism including a feed sprocketfor advancing a web through the printer, a line feed bar intermittentlyoperable for imparting step-by-step rotation to said sprocket, a drivepawl on said bar, a ratchet driven one step from a normal position bysaid drive pawl each time said line feed bar is actuated, spring meansfor urging said ratchet to return to said normal position, a retainingpawl for holding said ratchet in a position to which it has been steppedby said drive pawl, an auxiliary sprocket driven by said web, cam meansfixed to said auxiliary sprocket for disengaging said retaining pawlfrom the ratchet each time the web drives the auxiliary sprocket onestep, an alarm actuating lever fixed to said ratchet, and alarm meansactuated by said alarm actuating lever upon a predetermined number ofoperations of said line feed bar coupled with failure of said auxiliarysprocket to be driven by said web.

5. A telegraph printer according to claim 4 wherein the auxiliarysprocket and cam means are mounted on a stud shaft that is bodilymovable from a position where the auxiliary sprocket on it is in thepath of the web to a position where the auxiliary sprocket is out of thepath of the web and said retaining pawl is disengaged from the ratchetby movement of said auxiliary sprocket to facilitate inserting a webinto the printer.

6. The combination according to claim 5 wherein said ratchet retainingpawl has a second pawl pivotally mounted on it for engagement with theratchet when the stud shaft is moved to a position to carry theauxiliary sprocket out of the path of the web.

7. In a telegraph printer, line feed mechanism including a feed sprocketfor advancing a web through the printer, a line feed bar intermittentlyoperable for imparting stepby-step rotation to said sprocket, a drivepawl on said bar, a ratchet device driven from a normal position by saidpawl one step each time said line feed bar is actuated, means forresiliently urging said ratchet to return to said normal position, areset lever for blocking the return of said ratchet to normal position,means driven by the web for moving said reset lever out of blockingrelation with respect to said ratchet each time the web drives the meansdriven by the web one step, and alarm means actuated by said ratchet ifthe reset lever is not moved out of blocking relation to the ratchet fora predetermined number of operations of said bar.

8. In a telegraph printer, line feed mechanism including a feed sprocketfor advancing a web through the printer, a line feed bar intermittentlyoperable for imparting stepby-step rotation to said sprocket, a drivepawl on said bar, a ratchet driven one step from a normal position eachtime said line feed bar is actuated, spring means for urging saidratchet to return to said normal position, a retaining pawl for holdingsaid ratchet in a position to which it has been stepped by said drivepawl, an auxiliary sprocket driven by said web, cam means fixed to saidauxiliary sprocket for disengaging said retaining pawl from the ratcheteach time the Web drives the auxiliary sprocket one step, an alarmactuating lever fixed to said ratchet, and alarm means actuated by saidlever upon said lever being moved through a predetermined are due tofailure of the auxiliary sprocket to be driven by the web for apredetermined number of operations of the line feed bar.

9. A web feeding mechanism for telegraph printers including means forengaging a web to advance it through the printer, a line feed memberintermittently operable for imparting step-by-step movement to saidmeans engaging the web, means for engagement with the web to be drivenby the web each time the web is advanced, a storage member movable onestep by said line feed member each time said member operates, means forholding said storage member in the position to which it is moved, andmeans on the means driven by the web for disabling the holding meanseach time the means to be driven by the web is moved by the web.

References Qited in the tile of this patent UNITED STATES PATENTS

